Combined fluid pump and indicator



Nov. 3, 1959 H. coLMAN ETAL COMBINED FLUID PUMP AND INDICATOR Filed Nov22, 1954 R u. D 5 n Am ,www1

I., mm R w nited States PatentY COMBINED FLUID PUMP AND INDICATOR lHarry Colman, Ormond, near Melbourne, Victoria, and Raymond LawrenceFowler, Pascoe Vale South, near Melbourne, Victoria, AustraliaApplication November 22, 1954, Serial No. 470,466

Claims priority, application Australia December 4,1953

2 Claims. (Cl. 10S-1) This invention relates to a methodof and means forindicating the presence of water in petrol tanks and it refersparticularly to means for indicating the presence of water inunderground petrol tanks (such as are customarily installed at garages,airports and other locations) and in other petrol tanks where thecontents are not normally visible.

Itis commonly known that water does collect in petrol tanks,particularly in underground petrol tanks. Such` water as does collect ina petrol tank remains at the bottom of the tank and the volume of waterin said tank gradually increases, duc largely to condensation ofmoisture from the air. `As a result, it is generally considerednecessary to have the outlet opening of the petrol tank located adistancel above the bottom of the tank; so that the petrol drawn fromthe tank will be free of Water. But the presence of such water at thebottom of a petrol tank has serious disadvantages and it is generallyconsidered advisable, especially when the petrol is to be used inaircraft, to clear out any water from a' petrol tank as soon at itcollects.

Furthermore, water sometimes collects in the petrol tanks ofaircraft-either from condensation or as a ref; sult of being pumped intothe aircraft petrol tank with petrol from a tanker. The presence of,water in an aircraft petrol tank can have very serious results, and" inthe past it has been the cause of many serious accidents.

It has` been well' known for many years that the located in the tank dueto changes in the liquid between 2,910,946 Patented Nov. 3, 1959 r; 2And another object is to provide means for detecting the presence ofwater in a petrol tank or container and for ejecting the accumulatedwater from the container; `The in-vention devised with these and otherobjects in View resides, broadly, in the provision of proximity relayapparatusresponsive to capacitance changes and a vsheathed cable, thecable being connected to one ter- (or the complementary member) will beindicated by the; proximity relay apparatus.

Y When the apparatus is to be installed in an underground, petrol tankthe sheathed cable is connected to a sensing element and the proximityrelay is also connected-electrically to the tank itself (if the tank bemade of an electrical conducting material), or to a second element heldin spaced relationship with the sensing element (if the tank be made ofa non-conductor). The sensinggelement is so mounted that when fitted inan underground petrol tank the element is supported a relatively -shortdistance from the bottom of the tank. Further, there may be provided asupport for the cable and/organy suitable mounting for the sensingelement. Further,there may be employed any suitable electricalconnectionsand, if required, any suitable electrical equipment foramplifying signals.

The electrical apparatus may be connected to pumping apparatus in suchmanner that when the presence of water is detected the pump apparatuswill be set in operation to eject the accumulated water. Alternatively,there may be provided pumping apparatus operable independently when thepresence of water is indicated.

' lIn order that the invention may be clearly understood and readily putinto practical veffect we shall now describe, With reference to theaccompanying drawings, a general form of the apparatus and severalparticular applications of the invention. In these drawings:

the terminals, the resistance of water or apetrol-water mixture diteringfrom that of petrol. However, this apparatus has not been acceptable forthe reason that it, can prove to be dangerous, and the likelihood ofspark-` ing-and consequent 'explosion of the petrol-is relatively high.

This invention'has'been devised particularly With the'` object ofproviding improved apparatus for use in detecting,and indicating, thepresence of water inv petrol. A further object of the invention is toprovide apparatus for the purpose stated which willb'e extremelyelective and safe in operation, relatively economical to manufacture andto install, and of relatively simple construction. l i

Yet another object is to provide apparatusvfor the purpose stated whichwill be usable in'petrol tanks made of non-metallic material. A stillfurther object is to devise apparatus usable for detecting, andindicating, 'the presence of water in suspension in,petrol, or thepresence of water ina petrol pipeline. l

. Fig.kv l is `a diagrammatic illustration of apparatus according to theinvention for detecting the presence of waterin a petrol tank;

Fig. 2 shows, in vertical cross-section, the sensing head in relation`to the bottom of a petrol tank;

Fig. 3 is a circuit diagram of the proximity relay;

' Fig. 4 depicts the connections for use when the apparatus isto be usedfor operating a motor or other apparatus;

Fig. 5 illustrates a form of apparatus made according to the inventionand incorporating a hand pump;

Fig. 6 is a perspective view of the lower end of the apparatusillustrated in Fig. 5.

Referring initially to Figs. 1, 2, 3 and 4 the apparatus P for detectingthe presence of water in a petrol tank 11 an kalternating current supplysource, the terminals 15 and 16 for connection to the tank 11 and theprobe-indicated generallyin Fig. l by the reference 17. When a shieldedcable is used for connecting to the probe one end of the shield maybeconnected to terminal 15 (the other end being earthed or connected tothe tank 11) and the inner wire is connected to the terminal 16. Theprobe 17 comprises a sensing element 18 to which is connected a cable 19covered with insulating material The element 18 isv located within aprobe head 21 O having at its lower end a series of spaced lugs 22, andit is held in place, and insulated from the probe head 21, by a filling23 of insulating material-as a synthetic resin or plastic insulatingmaterial.

The probe hea-d 21 is fastened to vone end of a length of tube 24 madeof a conducting material, as a length of copper tube. The upper endportion of the probe head 21 is screw-threaded to receive a flare nut25, and it is chamfered at 26. The lower end of the tube 24 is ared orswaged outwardly at 27 so that it is conveniently clamped between thechamfered end 26 of the probe head 21 and the tapered surface of the arenut 25.

Fastened to a manhole cover 28 mounted in the top of the tank 11 is aninternally screw-threaded socket 29. A reduction bush 30, having anaxial opening of such a size as to be adapted to receive neatly theupper end portion of the tube 24, is screwed into the socket 29. Theupper end portion of the tube 24 is clamped firmly in the reduction bush30 by means of a ring seal 31 and a bush 32 which is screwed into theupper end portion of the reduction bush 30, and the insulation-coveredcable 19 is clamped firmly within the bush 32 by means of a second ringseal 33 and a nut 34, the latter being screwed into the upper end of thebush 32.

The probe head 21 is thus held in fixed relationship with the cover 28,and the cable 19 is securely held at its lower end and where it passesthrough the top of the tube 24. Thus, -there is no strain on the cable19.

The tubef24 is of such a length thatthe sensing element 18 is held ashort distance from the bottom of the tank 411. The lugs 22 act aslocators to ensure that the sensing element 18 is held a desireddistance from the bottom of the tank, the apparatus being set up withthe lugs 22 in contact with the tank bottom.

When the apparatus is set up in the manner illustrated in Fig. l, withthe sensing element 18'correctly located near the bottom of the tank,the -terminal 15` of the proximity relay apparatus connected to the tank11 (either directly or by both the terminal 15 and the tank beingearthed) and the terminal 16 connected to the cable 19, then anyvariation incapacitance between the sensing element .18 and the tank 11will be indicated by the vcapacity-operated proximity relay apparatuswithin the box 12. Thus, if there be an accumulation of water-indicatedby the reference 35e-in the petrol 36, the presence of the water betweenthe element 18 and the bottom of `the tank will be indicated. l

The proximity relay apparatus has the circuit indicated in Fig. 3. Therelay indicated by the reference 37vhas terminals 378, 39, 40 and 41, ofwhich the terminals 38 and 39 may be connected to a motor for `driving apump in such manner that when the relay is operative to indicate thepresence of Water in the petrol the motor -will be set in operation todrive the pump so as to eject .the water from the vtank 11. Theterminals 40, 41 may be connected to any suitable indicating means-as anelectric light globe, or a buzzer. Alternatively, `the apparatus may beset up so that a pump will be shut olf when the presence of water isdetected in the petrol. This will be donelwhen the apparatus is includedin a pipe line throughwhich petrol is being fed to the petrol tank. n ny Referring now to Figs. and 6 the apparatus `depicted thereincomprisesa tubular member 42 having aprobe head 21 fastened lto itslower end by means of theV nut 25. This probe head has lugs 22 at itslower end but whereas the sensing element in the constructionpreviouslydescribed, is in the form of a disc, the vsensing element inthis construction is in the form of a flat ring 43 fastened to, butinsulated from, the probev head 21. Ther cable19 is secured to the outersurface of the member 42 and it fits through an opening provided in thenut 25, being secured at its lower end to the ring 43.

The opening 44 in the ring 43 permits flow of liquid to a pump plunger45 of any suitable type.

This plunger 45 is fastened to one end of a rod 46 and a handle 47 issecured to the other end of that rod. Thus, the rod 46 may be movedvertically relative to the tubular member 42. An `outlet nozzle 48 isprovided near the upper end of the tubular member 42 so thatliquidpumped upwardly through-.that member 42 by the operation of -thejpumpplunger 45 may escape from within the member 42.

The vproximity relay apparatus 12 is mounted on a bracket '49 Vfastened4to thetubular member 42 near its upper end and a handle 50 is connectedto the bracket 49 so as to provide a convenient means of holding theapparatus.

The indicating and pump apparatus illustrated in Figs. 5 and 6 may beconveniently carried byan operator and used to test for the presence ofwater in petrol containersas 44 gallon drums-and to eject water whichmay have accumulated'in such containers.

It isto beV noted that in this apparatus the tubular member 42 will beconnected to the terminal 15 of the apparatus I12 Vand whenthe-apparatus is in use the lugs 22 at the lend of the probe head 21,-in making contact with the the interior of the tubular member 42,wherein i'sttcd 75 bottom ofthe container, will alsoeifect theelectrical connectionof the apparatus 12 to 'the petrol container.

'If desired, a'spacin'g member may be adjustably tted tothe lower end ofthe probe head 21 so that the distance between the sensing element 18and the bottom of the petrol tank 11, when the apparatus is fitted inposition, may be adjusted -to suit Vany particular requirements. We havefound that a distance of 1/2" between the sensing element and the bottomof the'tank is suitable for most purposes. l

[,In another -embodiment of thejinvention two sensing elements arettedkto the lsame pipe, so that they are spaced ashort distanceapart Theterminals 1,5, 16 of the ,proximity relay apparatus are then connectedto the two sensing elements. This apparatus vmay be mounted so .that thetwo sensing elements are a suitable distanceV from the bottom of thetank. The device vmay then be used to detect water suspended in thepetrol, as it has been foundthat suspended water provides .a sucientchangelinfdielectric vconstant to operate the level control unit. l

In another embodiment of the invention two sensing elements are mountedin a pipe or hose which is `used in the delivery of the petrol from thetank, so as to indicate the presence of water in the petrol flowingthrough the pipe or hose. a

The device has beenfound sulitable for use in the detection of water orother foreign substances in other media, such as kerosene or whitespirit, and hence the word .petrol should be taken to include allpetroleum products, and the term water to include yall such foreignsubstances of dielectric constant appreciably differ'- ent fromthat ofpetrol It is to be noted-that Vin the form :of the invention illustratedin Fig. 2 the sensing element 18` is provided with a lcovering ofinsulating material. This is doneto reduce the risk of tire due to aninsulation failure in the external circuit, which failure could cause aspark be'- tween the element'andthe tank.

`If apparatus according to the invention be incorporated in a tank at alocation whereat the electricity supply is not at,y the normal A.C.mains voltage, then it may be necessaryto modify the apparatus. Forexample, if it be desiredto build water detection apparatus into thepetrol tanks of aircraft, then the capacity operated relay devices willhave'to bemodied to make them suitable for operation on'directcurrent-from the aircraft supply systemand there will be incorporated inthe circuit from the valve of the capacity operated relay devices to thesolenoid type relay a current amplifying valve of standard type so as toprovide fora sufficiently high value of current. A single sensingelement may be used if the tank be of inetal, but if the tank benon-metallic on the inside then two sensing elements vwill be required,one connected to the plate *or the lgrid of the oscillator valve and theother to the cathode circuit.

It will be appreciated that the manner of installing the apparatus in apetrol tank will depend largely upon the nature of the tank and upon thelocationthereof. All such modifications are to be deemed to be includedWithin the ambit of the invention.

What We claim is:

1. Apparatus for detecting the presence of water in petrol including apetrol tank, proximity relay means responsive to capacitance changes andhaving an earth terminal and an active terminal, the earth terminalbeing connected electrically to the bottom of the tank, a pump includinga cylinder projecting into the tank, said pump having an outlet near itsupper end and an inlet near the lower end, a piston adapted to drawwater upwardly within the cylinder and to expel it through such outlet,a probe housing at the lower end of the cylinder, a probe mounted insaid housing and electrically insulated therefrom, lugs projecting fromthe lower end of the probe housing to contact the bottom of the tank,the thus mounted probe thereby being held a short distance above thebottom of the tank, and an electrical connection between the activeterminal and the probe, the proximity relay means being adapted todetect water in the lower portion of the tank and the pump beingoperable to expel the same.

2. Apparatus for fdetecting the presence of water in petrol including apetrol tank, proximity relay apparatus responsive to capacitance changesand having an earth terminal and an active terminal, the earth terminalbeing connected electrically to the bottom Iof the tank, a probe housingmounted Within thev tank at the lower end of a pump, the pump having acylinder to which the probe housing is tted, an outlet near the upperend of the cylinder, an inlet near the lower end of the cylinder, and apiston adapted to draw water upwardly from the lower end of the cylinderand to expel it through that outlet, a probe mounted in the probehousing and electrically insulated therefrom, lugs projecting from thelower end of the probe housing into contact with the bottom of the tankso that the probe is spaced a set distance from the bottom, and anelectrical connection between the active terminal and the probe, theapparatus being so arranged that the proximity relay apparatus isadapted to indicate variations in dielectric constant of the material inthe tank between the probe and the bottom of the tank.

References Cited in the tile of this patent UNITED STATES PATENTS`861,003 Wagner July 23, 1907 1,033,173 Hoaglin July 23, 1912 1,506,197Nicholas Aug. 26, 1924 2,018,687 Sims Oct. 29, 1935 2,023,586 HarrodDec. 10, 1935 2,051,180 Ruzicka Aug. 18, 1936 2,204,998 Ryan et al June18, 1940 2,329,728 Samiran Sept. 21, 1943 2,371,339 Markwart Mar. 13,1945 2,375,084 Coroniti et al. May 1, 1945 2,428,700 Eilenberger Oct. 7,1947 2,463,703 Legler Mar. 8, 1949 2,573,172 Ennis et al Oct. 30, 1951FOREIGN PATENTS 368,998 Great Britain Mar. 17, 1932

